It is well known to carry out mining operations in a sea bed particularly along a continental shelf or other bodies of water that are shallow enough for support structures of the kind that have a number of upstanding legs resting upon the bottom of a body of water connecting with a frame construction supporting a platform, the legs being so associated with the frame construction as to be separately displaceable relative to the frame construction by a combination of individual lifting/lowering movements together with horizontal movements of the platform the result of which moves the structure from one user location to another.
As is indicated above a particular use of such structures is to undersea mining activities that are in practice carried out from the platform which as mentioned is located above the water body surface, i.e., the sea surface.
Undersea mining activities involve a number of different modes of operation that require equipment located above water level for controlling apparatus that is in operation submerged and designed for performing a required under seas mining operation